The manufacture of extremely large and often delicate objects becomes difficult in that they must often be transported during manufacture as well as taken from the place of manufacture for inspection, modification and eventually for use. These objects often must be transported without overloading the wheels of the transporter from floor undulations or torquing or otherwise stressing the skin of the object. In the past, special equipment has been manufactured for this transport on an individual customized basis or, as an alternative, a special extremely smooth and level supporting floor or surface has been prepared, allowing the transportation by air bearings or the like. It becomes immediately obvious that the movement of devices upon specifically and individually constructed support vehicles as well as devices which require a specially prepared underlayment becomes extremely expensive and impractical for many types of industrial applications. A more universal approach is indicated.
Patented prior art known to the present inventor dealing with modular, wheeled steerable transporters for large objects includes U.S. Pat. No. 3,280,931 granted to Cahill et al, on Oct. 25, 1966, which discloses multi-wheeled module units which may be individually or as a group placed beneath a heavy load which need to be transported. The disclosure provides a means for synchronized steering of the various wheeled modules to assure tracking of the units.
U.S. Pat. No. 3,387,684 granted to Belke, on Jun. 11, 1968, discloses an apparatus for accurate tracking in a large vehicle having multiple wheel assemblies independently suspended from the vehicle hull or main frame. Individual wheel units may be raised or lowered.
U.S. Pat. No. 3,572,458 granted to Tax, on Mar. 30, 1971, discloses an all-wheel steering system for a multi-wheeled vehicle including cams which allow for a different turning angle for each wheel, required to prevent scrubbing.
U.S. Pat. No. 3,632,129 granted to Bear, on Jan. 4, 1972, discloses an axle assembly which prevents the lateral skidding of the tandem wheels. The wheels are mounted upon an elongated beam which allows the wheels to be selectively turned, and further includes a spring-loaded centering device urging the wheel sets to a tandem configuration.
U.S. Pat. No. 3,773,348 granted to Davis, on Nov. 20, 1973, discloses a vehicle suspension assembly including a shock absorbing suspension strut and a forward and rearwardly extending trunion which allow axial, radial and vertical movement of the wheels.
U.S. Pat. No. 3,792,745 granted to Files, on Feb. 19, 1974, discloses a vehicle having a frame and four individual traction carriages and power means for steering the carriages. Feedback controls coordinate the parallel positioning of the carriages as required.
U.S. Pat. No. 4,049,071 granted to Stedman, on Sep. 20, 1977, discloses a dual wheel suspension and drive arrangement for the main frame of a truck, wherein the forward end of a subframe is secured by a ball and socket and the rear end by a suspension cylinder. A pair of road wheels are rotatably mounted on either side of the side frame and driven by a common drive axle.
U.S. Pat. No. 4,200,162 granted to Tax, on Apr. 29, 1980, discloses a bridge portion for a traveling gantry wherein each corner of the platform is supported by at least one road wheel and steering devices permit the several wheels to be individually turned about their respective axes.
U.S. Pat. No. 4,372,406 granted to McColl, on Feb. 8, 1983, discloses a load-carrying vehicle having front and rear quad-wheel assemblies dually connected to a centrally disposed elongated bed frame, permitting lateral rotation of the assemblies about a roll axis disposed below and parallel to the longitudinal axis of the bed frame.
U.S. Pat. No. 4,417,634 granted to Quaeck, on Nov. 29, 1983, discloses an elevating transport vehicle carried by steerable idler bogies.
U.S. Pat. No. 4,678,203 granted to Rohner et al, Jul. 7, 1987, discloses an air spring including a sensitive control device to isolate vibrations, generated in the air spring, from the vehicle.
U.S. Pat. No. 4,702,842 granted to Oswald et al, on Oct. 27, 1987, discloses an all-terrain vehicle which includes a system for controlling vehicular functions; including providing hydraulic fluid to the hydraulic motor on one side of the vehicle independent of the hydraulic motor on the other side of the vehicle; controlling the vertical positions of the wheels on opposing sides of the vehicle, and others.
U.S. Pat. No. 4,729,448 granted to Sullivan, on Mar. 8, 1988, discloses a planetary drive axle including an offset trunion bracket, permitting the steering actuator to move in a horizontal plane while the axle oscillates in a vertical plane.
U.S. Pat. No. 4,872,702, granted to Medley, on Oct. 10, 1989, discloses a suspension system for high-capacity hauling vehicles including a gas/fluid system to self-level the vehicle, however the operator may manually override the feature to raise and lower the vehicle body.
U.S. Pat. No. 4,886,285 granted to Horbach et al, on Dec. 12, 1989, discloses a load-supporting plurality of transporter frames having wheels each of which is mounted for pivot at one end and at the other end by hydraulic cylinder and wherein all the hydraulic cylinders of that group are connected to one another and to a pump by means of a connecting line.
U.S. Pat. No. 4,934,733 granted to Smith et al, on Jun. 19, 1990, discloses a wheel suspension system utilizing a pivotally mounted wheel and hydraulic cylinder or air bag whereby the load floor of the vehicle may be located beneath the center line of the vehicle.
U.S. Pat. No. 5,016,912 granted to Smith et al, on May 21, 1991, deals with the same subject matter as U.S. Pat. No. 4,934,733 discussed herein above.